ELISA: A small balloon Experiment for a Large Scale Survey in the Sub-millimeter

This paper presents the technical aspects and scientific objectives of the balloon-borne Experiment for Large Infrared Survey Astronomy (ELISA). The emphasis is put upon the synergies existing between the ELISA project and future space missions, both with respect to technical and scientific aspects. ELISA is a small balloon project for an experiment dedicated to measure the Far-Infrared to Sub-millimeter continuum emission of dust over a large fraction of the sky, with unprecedented sensitivity and angular resolution. The primary mirror of the telescope, similar to the one used for the Top-Hat mission, will have a diameter of 1 m, ensuring an angular resolution of about 3.5′. PACS-type bolometer arrays will be used in four photometric bands centered at 170, 240, 400, and 650 μm and providing a 22′×45′ instantaneous field of view per channel. A liquid He cryostat will host the cold optics, including the secondary mirror of the telescope, as well as the detectors, which will be cooled to 0.3 K using an He3 ...